apex has definitions from the field of astronomy
1
[ noun ] the highest point (of something)

Synonyms

peak acme vertex

Examples

"at the peak of the pyramid"

Used in print

(Arlin Turner, "William Faulkner, Southern Novelist"...)

The tradition reached its apex , perhaps , in the works of Thomas_Nelson_Page toward the end of the century , and reappeared undiminished as late as 1934 in the best-selling novel So_Red_the_Rose , by Stark_Young .

Related terms

extreme_point crown roof_peak

2
[ noun ] (astronomy) the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars
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